Mark was always a hill man. He maintained that planting in hills allowed the soil in the hill to be surrounded by heated air, and thus to be warmer than just flat dirt. Many plants love the heat of hills. He was very successful with his hills.

But the disadvantage of hills is that they allow, even promote, water to run off and away.

I was always a pit or trench man. I maintained that in our very dry climate plants should be placed in pits. Pits trap the water for the plants.

The disadvantage of pits is that heat concentrates on the sides, away from plant roots.

But raised beds seemed to offer the best of both hill and pit planting. By raising the soil, and thus the roots, plants can capture heat from the side of the box. By not filling the box completely full of soil, one can then flood irrigate. Thus you can have the best qualities of both hill and pit.

Here is the type of raised beds we built for our garden. We made them 3 feet by 3 feet because 6 foot cedar fence boards were on sale at our local lumber yard. This proved to be very fortunate. We found we really like the 3 x 3 size. Mel Bartholomew recommends 4 x 4 beds, but we think the 3 x 3 beds are easier to reach across when seeding, weeding, and harvesting.

Building a box for a Raised Bed

We built our first boxes from 6 foot X 5 1/2 inch X 3/4 inch cedar
fencing slats. It was a lucky mistake. The 3/4 inch slats did not hold up. But we found
that we really liked the 3 foot X 3 foot, and 3 foot X 6 foot size of the beds, much better
than we would have liked 4 foot wide beds. Now days we build bed boxes from 2 X 6 lumber.
2 X 6 is actually 1 1/2 inches by 5 1/2 inches when you measure it. I like to get 2 X 6 studs.
They are considerably less expensive than regular 2 X 6s, they do the same job, and yeild
a little less waste.

Here are the beds in mid-September, 2001. Our paths are 18 to 24 inches wide.

The other advantages to raised beds:

You never walk on the soil used for growing. You never compress or pack the soil that plants need to be as loose as possible, for root development.

You concentrate water and fertilizer onto the desired plants, not the weeds. Weeds tend not to grow in the paths because there is no water there.

Weeding is easier because you can concentrate on just a few beds at a time. As summer progresses the desired plants crowd out any weeds in the beds.

Looser soil allows for much more intensive planting. You can crowd plants and use every square inch of the growing surfaces.

Watering is more effective and even. Yeilds are bigger than in conventional gardening.

Soils can be mixed and adjusted in each bed, before planting, to meet the special requirements of the plants going into specific beds.

Hoses are easily kept off of plants when watering.

Trellising, plastic mulching, shading, covering, are all easier with the raised beds.

Intensive Planting

Now the other aspect to raised beds:

As I mentioned above, intensive planting was first developed by the French. The super - loose soils of raised beds allow much easier root development than the average garden. Therefore the space that is 'lost' in the paths between the beds is made up by planting seeds and setting in plants much closer than is normal.

For instance, it is commonly recommeded in books that bush beans be planted in rows 9 to 18 inches apart. In his book Square Foot Gardening, Mel Bartholomew recomends planting bush beans at the rate of 9 per square foot in a grid. I like to plant in rows. This last year (2001) I planted my rows of bush beans in the raised beds about 4 inches apart. That was probably a bit too close. So next year I will plant my rows in the raised beds at two-per-foot, or 6 inches apart. Carrots and Radishes can go in at 4 or 5 rows per foot. A rule of thumb is to plant one to three more rows-per-foot than normal when planting raised beds.

Bartholomew plants 4 tomato plants per 4' x 4' bed, which gives each plant 4 square feet of space. This recent year (2001) we planted big main tomato plants at the rate of 4 per 3' x 3' bed, or 2.25 square feet per plant. We were very successful with those plants which grew over five feet tall. Our pepper plants do well at 1 per square foot in a 3' x 3' bed, or 9 plants in a bed.

We seem to be able to plant a bit more intensively here in Wyoming than would be possible in other parts of the country. The reason for this is simply that our plants don't get as big as they would at lower altitudes, and so they take up less space.

The one downside to intensive planting is that it uses soil nutrients at a much faster rate. So soil improvement is a must each year.

Why do intensive planting:

Bartholomew is fond of saying that intensive planting gives twice the yeild in half the space. Our experieces with it seem to confirm that statement. Here is why it works. A tomato plant, unstaked and with ideal growing conditions, will take up between 9 and 24 square feet of horizontal space. We have actually done this.

The same tomato plant, grown veritcally, will need only one third to one twelth of horizontal space that the plant grown horizontally would use. By using less square footage in growing one kind of crop, you can then use the space saved to grow a lot more of that variety, or you can grow varieties you would otherwise not have space for. Given good nutrients and enough water, we have found that raised beds with intensive planting have given us our best harvests ever.

How to get exact spacing:

The Rake - Spacer

I have invented a little device that helps me space rows in beds quickly and exactly. I cut pieces of plywood exactly one foot wide. Into the long sides of the boards I cut teeth spaced in ranges of from one to five teeth-per-foot. To save on lumber I cut teeth on both long sides.

I then pull the rake-spacer through the loose level soil of my prepared bed. It leaves straight and even grooves in the soil that are ready to accept seeds.

Then, by placing a rake-spacer lengthwise in (or in the direction of) a groove, I can get precise spacing for the seeds in that groove at 1, 2, 3, 4, or 5 seeds per foot.

Using old tires for raised beds:

Before this season (2002) we had always used wooden boxes for raised beds. This year we tried something new: old tires. We found that tires get the soil too hot for many plants. However, Onions , squash, pumpkin, and cauliflower responded well to the tires. Carrots and corn did not. The average 15 inch tire gives you about 6 square feet of planting space. The walls, or tire tread, give extra heat to the contained soil. Tires seal themselves with the soil below and so they never leak water. This allows for flood irrigation.